Backyard Biodiversity

By Kristin Friedrich

The following story is contributed by the Natural History Museum of Los Angeles County, one of Natural History magazine’s Museum Partners. Members of any of our partner organizations receive Natural History as a benefit of their museum membership. The Natural History Museum of Los Angeles County, which opened its doors to the public in 1913, is the largest natural and historical museum in the western United States, safeguarding more than 33 million diverse specimens and artifacts. Its main exhibition halls, located at 900 Exposition Boulevard, feature grand dioramas of African and American mammals, rare dinosaurs and fossils, marine animals, Pre-Columbian culture, gems and minerals, and historical artifacts from California and Southwest history, as well as early Hollywood memorabilia. The Museum is also an active research center, spanning living and fossil invertebrates, vertebrates, mineralogy, anthropology, and history. The Natural History Museum also includes the William S. Hart Ranch and Museum, once the home of that silent film actor, and the Page Museum at the La Brea Tar Pits. As you read this, the Natural History Museum’s Entomology Department is collecting insects in the rainforests of Costa Rica and Thailand. But last year, Curator Dr. Brian Brown also set up a Malaise trap in a locale slightly less exotic—his Los Angeles backyard.

As you read this, the Natural History Museum’s Entomology Department is collecting insects in the rainforests of Costa Rica and Thailand. But last year, Curator Dr. Brian Brown also set up a Malaise trap in a locale slightly less exotic—his Los Angeles backyard.

The trap, named not for the feeling but for its Swedish entomologist inventor, René Edmond Malaise, consists of a tent-like apparatus and an attached collecting bottle. Using it in his yard, Brown procured an assortment of familiar insects, as well as an unusual looking robber fly, about a centimeter long.

He thought little of it, but as entomologists are wont to do, he dropped it in some alcohol and handed it off to a colleague when the two were at the same biology conference in Chicago. The recipient, the Field Museum’s Dr. Torsten Dikow, is a robber fly expert. “There’s not that many fly experts,” Brown says. “We tend to know each other.”

Dikow contacted Brown a few weeks later, astounded. The backyard fly was a new species of the genus Leptopteromyia, previously known only in an area spanning from Central America to southern Texas, and certainly not from the U.S. west coast. “What is interesting about this genus,” he wrote to Brown, “is that the larvae are known to develop in webs of Embioptera — an enigmatic group known as web spinners. Do you have Embioptera in your backyard? Is there any chance you got more of these?”

In fact, Brown did have those strange web spinners in his backyard, and even better, he found several more specimens of the new species in subsequent trap samples. The flies are in a family popular with amateur collectors and had eluded capture. “Probably they are not rare,” Brown says, “just unnoticed and previously unexpected.”

For fun, and to provide a theme for a Museum special event, Brown bragged that he could find unknown fly species from other backyards as easily as his own. Last spring, he set up a trap in a Museum Trustee’s Brentwood backyard. The very first specimen he put on a slide and looked at under the microscope was a new species of the phorid flies he studies. “The second specimen I pulled out was a species that had only been found before in Europe, and then another specimen I pulled out, we identified as a species that had only been collected off the coast of Africa.”

The very first specimen he put on a slide and looked at under the microscope was a new species of the phorid flies he studies. “The second specimen I pulled out was a species that had only been found before in Europe, and then another specimen I pulled out, we identified as a species that had only been collected off the coast of Africa.”